Jeffrey Eugenides’ Middlesex (Knopf Canada) is the eighty-year saga of the Stephanides family, who immigrate to America from Greece. It is a conventional tale, except for a few crucial details. At the heart of the action is a gene, a recessive mutation of the fifth chromosome, passed down through the inbred inhabitants of a village to the narrator, Calliope, who at fourteen discovers that she is both male and female. Biology and identity hold the story together, and Eugenides makes a strong case that science alone cannot explain personality—in fact, humans are apparently no more genetically diverse than mice. Middlesex lacks the atmosphere and unusual structure of Eugenides’ first novel, The Virgin Suicides. As in many family sagas, some of the action loses its romantic appeal as the story approaches the present day, and it was the scenes of the Stephanides siblings in war-torn Asia Minor that captured my imagination most thoroughly. But Eugenides worked on this novel for a decade, and the effort shows—every historical situation is utterly compelling, each character drawn to perfection.